The present invention relates to an operation apparatus, a standby apparatus, operation and standby systems, and operation and standby control methods and more particularly to an operation apparatus, a standby apparatus, operation and standby systems, and operation and standby control methods that can avoid an error caused by noise during failure management.
In conventional operation and standby systems disclosed in Japanese Patent Application Laid-open Hei No. 11-338,724, the operation system and the standby system send heartbeat signals to each other in order to confirm the operation status of the other system. When the standby system does not receive a heartbeat signal from the operation system after a certain period of time, it is determined that the operation system must have a failure.
In the conventional operation and standby-systems, the operation and standby systems have a problem. The problem is that there is no countermeasure for noise. For example, when a failed operation system is replaced by a hot-swap, noise is generated in the signal transmission path between the operation system and the standby system. The standby system will have an error due to this generated noise because these operation and standby systems do not have a countermeasure for noise.
The specification of I2C bus is described in “The I2C Bus from Theory to Practice, Ed. BK&DISK, written by Dominique Paret and Carl Fenger, published by WILEY”.